Charged particle beam apparatus having needle probe that tracks target position changes

ABSTRACT

A charged particle beam apparatus includes: a charged particle beam column; a detector configured to detect secondary charged particles; an image processor; a display device; a needle arranged in an irradiation area of charged particle beam; a needle actuator; a user interface; and a controller configured to control the needle actuator to actuate the needle in accordance with a target position that is set by the user interface. The controller controls the needle actuator to move the needle to track a change of the target position that is set by the user interface.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority from Japanese Patent Application No.2014-024421, filed on Feb. 12, 2014, the entire subject matter of whichis incorporated herein by reference.

BACKGROUND

1. Technical Field

The present invention relates to a charged particle beam apparatus.

2. Description of the Related Art

Conventionally, a charged particle beam apparatus has been known inwhich a needle that is movable by an actuator is disposed in theapparatus, an observation image obtained by a charged particle beam isdisplayed on a display device, and the needle is moved to a positionthat is indicated in the observation image by a user interface operatedby the operator. An example of such apparatus is disclosed inJP-A-2000-147070.

In the apparatus of the background art, the current position (startpoint) of the needle and the target position (end point) are designatedin the observation image on the display device by using the userinterface, whereby the needle is moved from the current position to thetarget position. In order to move the needle to the target positionwhile passing through a plurality of way points, therefore, the startand end points must be designated for each of the way points, therebycausing a problem in that the operation is complicated.

SUMMARY

The present invention has been made in view of the above-describedcircumstances, and one of objects of the present invention is to providea charged particle beam apparatus, in which the operability is improvedfor a case where a needle is to be moved by the operator while theoperator views an observation image obtained by a charged particle beam.

According to an exemplary embodiment of the present invention, there isprovided a charged particle beam apparatus including: a charged particlebeam column configured to irradiate an irradiation target with a chargedparticle beam; a detector configured to detect secondary chargedparticles emitted from the irradiation target by the irradiation withthe charged particle beam; an image processor configured to produceimage data indicating a two-dimensional distribution of intensity of thesecondary charged particles detected by the detector; a display deviceconfigured to display the image data produced by the image processor; aneedle arranged in an irradiation area of the charged particle beam; aneedle actuator configured to actuate the needle; a user interfaceconfigured to receive an operation input of an operator and set a targetposition of the needle on the image data in accordance with theoperation input; and a controller configured to control the needleactuator to actuate the needle in accordance with the target positionthat is set by the user interface. The controller controls the needleactuator to move the needle to track a change of the target positionthat is set by the user interface.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects of the present invention will become moreapparent and more readily appreciated from the following description ofillustrative embodiments of the present invention taken in conjunctionwith the attached drawings, in which:

FIG. 1 is a view showing a configuration of a charged particle beamapparatus of an embodiment of the invention;

FIG. 2 is a view showing an example of an operation screen and a displayscreen of the charged particle beam apparatus according to theembodiment;

FIG. 3 is a view showing an example of a change of the position of aneedle image which tracks the movement of a cursor on images data in thedisplay screen of the charged particle beam apparatus according to theembodiment;

FIG. 4 is a view showing another example of a change of the position ofthe needle image which tracks the movement of the cursor on images datain the display screen of the charged particle beam apparatus accordingto the embodiment;

FIG. 5 is a view showing another example of the operation screen anddisplay screen of the charged particle beam apparatus according to theembodiment;

FIG. 6 is a view showing an example of needle movement in sequentialmovement in the charged particle beam apparatus according to theembodiment; and

FIG. 7 is a view showing an example of needle movement in sequentialmovement in a charged particle beam apparatus of a third modificationaccording to the embodiment.

DETAILED DESCRIPTION

Hereinafter, a charged particle beam apparatus according to anembodiment of the invention will be described with reference to theaccompanying drawings.

As shown in FIG. 1, the charged particle beam apparatus 10 according tothe embodiment is provided with: a sample chamber 11, the interior ofwhich can be maintained in a vacuum condition; a stage 12 which can fixa sample S inside the sample chamber 11; and a stage actuator 13 whichmoves the stage 12. The charged particle beam apparatus 10 further has afocused ion beam column 14 which irradiates an irradiation target in apredetermined irradiation area (i.e., a scan area) in the sample chamber11 with a focused ion beam (FIB). The charged particle beam apparatus 10further has an electron beam column 15 which irradiates the irradiationtarget in the predetermined irradiation area in the sample chamber 11with an electron beam (EB). The charged particle beam apparatus 10further has a detector 16 which detects secondary charged particles(secondary electrons and secondary ions, or the like) R generated fromthe irradiation target by the irradiation with the focused ion beam orthe electron beam. The charged particle beam apparatus 10 further has agas supplying unit 17 which supplies a gas G to the surface of theirradiation target. The charged particle beam apparatus 10 further has aneedle 18 which is to be in contact with the sample S fixed to the stage12, and a needle actuator 19 which actuates the needle 18. The chargedparticle beam apparatus 10 is further provided with: a display device 20which displays image data due to the secondary charged particles Rdetected by the detector 16 and other data; a controller 21; and a userinterface 22.

The irradiation target of the focused ion beam column 14 and theelectron beam column 15 is configured by the sample S fixed to the stage12, the needle 18 existing in the irradiation area, and the like.

The charged particle beam apparatus 10 according to the embodimentirradiates the surface of the sample S configured by a semiconductorwafer, a semiconductor chip, or the like with the focused ion beam whilescanning, whereby various processes (etching and the like) of the sampleS by sputtering, and formation of a deposition film can be performed.For example, the charged particle beam apparatus 10 can performprocesses of: forming a cross section for cross-section observation by ascanning electron microscope, in the sample S; or forming a sample (forexample, a thin sample, or an acicular sample) for transmissionobservation by a transmission electron microscope, from the sample S.The charged particle beam apparatus 10 according to the embodiment isable to irradiate the surface of the irradiation target configured bythe sample S, the needle 18, and the like with the focused ion beam orthe electron beam while scanning, whereby the surface of the irradiationtarget can be observed.

The sample chamber 11 is configured so that the interior can beevacuated by an evacuating device (not shown) until a desired vacuumcondition is attained, and the desired vacuum condition can bemaintained.

The stage actuator 13 is housed in the sample chamber 11 in a statewhere the mechanism is connected to the stage 12, and moves the stage 12with respect to predetermined axes in accordance with a control signalsupplied from the controller 21. The stage actuator 13 is provided witha movement mechanism 13 a which moves the stage 12 in parallel along theX- and Y-axes which are parallel to the horizontal plane andperpendicular to each other, and the Z-axis which is perpendicular tothe X- and Y-axes. The stage actuator 13 is provided with a tiltmechanism 13 b which rotates the stage 12 about the X-axis or theY-axis, and a rotation mechanism 13 c which rotates the stage 12 aboutthe Z-axis.

The focused ion beam column 14 is fixed to the sample chamber 11 in sucha manner that, in the sample chamber 11, a beam emitting portion (notshown) faces the stage 12 at a position which is vertically above thestage 12 in the irradiation area, and the optical axis is in thevertical direction. According to the configuration, the focused ion beamcan be irradiated on the irradiation target such as the sample S fixedto the stage 12, and the needle 18 existing in the irradiation area,vertically downward from the upper side.

The focused ion beam column 14 is provided with an ion source 14 a whichgenerates ions, and an ion optical system 14 b which focuses anddeflects ions extracted from the ion source 14 a. The ion source 14 aand the ion optical system 14 b are controlled in accordance with thecontrol signal output from the controller 21, and the position,condition, and the like of irradiation with the focused ion beam arecontrolled by the controller 21. For example, the ion source 14 a is aliquid metal ion source using liquid potassium, a plasma ion source, agas field ionization ion source, or the like. For example, the ionoptical system 14 b is provided with a first electrostatic lens such asa condenser lens, an electrostatic deflector, a second electrostaticlens such as an objective lens, and the like.

The electron beam column 15 is fixed to the sample chamber 11 in such amanner that, in the sample chamber 11, a beam emitting portion (notshown) faces the stage 12 in a tilt direction which is inclined by apredetermined angle with respect to the vertical direction of the stage12 in the irradiation area, and the optical axis is parallel to the tiltdirection. According to the configuration, the electron beam can beirradiated on the irradiation target such as the sample S fixed to thestage 12, and the needle 18 existing in the irradiation area, downwardfrom the upper side in the tilt direction.

The electron beam column 15 is provided with an electron source 15 awhich generates electrons, and an electron optical system 15 b whichfocuses and deflects electrons emitted from the electron source 15 a.The electron source 15 a and the electron optical system 15 b arecontrolled in accordance with the control signal supplied from thecontroller 21, and the position, condition, and the like of irradiationwith the electron beam are controlled by the controller 21. For example,the electron optical system 15 b is provided with an electromagneticlens, a deflector, and the like.

The placement positions of the electron beam column 15 and the focusedion beam column 14 may be replaced with each other so that the electronbeam column 15 is placed in the vertical direction, and the focused ionbeam column 14 is placed in a tilt direction which is inclined by apredetermined angle with respect to the vertical direction.

The detector 16 detects the intensity of the secondary charged particles(secondary electrons and secondary ions, or the like) R emitted from theirradiation target such as the sample S and the needle 18 by theirradiation with the focused ion beam or the electron beam (namely, theintensity means the quantity of the secondary charged particles) on theirradiation target, and outputs information of the detected intensity ofthe secondary charged particles R. The detector 16 is placed at aposition which is in the sample chamber 11, and at which the intensityof the secondary charged particles R can be detected, such as that whichis obliquely upward with respect to the irradiation target such as thesample S in the irradiation area. The detector is fixed to the samplechamber 11.

The gas supplying unit 17 is fixed to the sample chamber 11 in such amanner that, in the sample chamber 11, a gas outlet (not shown) facesthe stage 12. The gas supplying unit 17 can supply to the sample Sgasses such as an etching gas for selectively promoting etching of thesample S by the focused ion beam in accordance with the material of thesample S, and a deposition gas for forming a deposition film by adeposition material such as a metal or an insulator on the surface ofthe sample S. For example, an etching gas containing xenon fluoride forthe sample S made of a Si material, water for the sample S made of anorganic material, or the like is supplied together with irradiation bythe focused ion beam to the sample S, whereby etching is selectivelypromoted. For example, a deposition gas of a compound gas containingphenanthrene, platinum, carbon, tungsten, or the like is suppliedtogether with irradiation by the focused ion beam to the sample S,whereby solid components decomposed from the deposition gas are causedto deposit on the surface of the sample S.

The needle actuator 19 is housed in the sample chamber 11 in a statewhere the mechanism is connected to the needle 18, and displaces theneedle 18 in accordance with the control signal supplied from thecontroller 21. The needle actuator 19 is provided with a movementmechanism (not shown) which moves the needle 18 in parallel along theX-, Y-, and Z-axes, and a rotation mechanism (not shown) which rotatesthe needle 18 about the center axis of the needle 18.

The controller 21 is placed outside the sample chamber 11, and connectedto the display device 20, and the user interface 22 which outputs asignal according to an operation input of the operator, such as a mouseand a keyboard.

The controller 21 generally controls the operation of the chargedparticle beam apparatus 10 by a signal which is output from the userinterface 22, that which is produced by a preset automatic operationcontrol process, and the like.

In accordance with the signal supplied from the user interface 22, thecontroller 21 controls the display device 20 to display various screens,and controls the needle actuator 19 to actuate and move the needle 18.

For example, the controller 21 converts the intensity of the secondarycharged particles R which is detected by the detector 16, into aluminance signal corresponding to the irradiation position on thesurface of the irradiation target (the sample S, the needle 18, and thelike) in the irradiation area, thereby producing image data indicatingthe two-dimensional distribution of the intensity of the secondarycharged particles R. Then, the controller 21 controls the display device20 to display a screen for performing operations such as expansion,contraction, movement, and rotation of the image data, together with theproduced image data. The controller 21 further controls the displaydevice 20 to display a screen for performing operations such as contactof the needle 18 in the irradiation area with a desired place, movementto a designated position, setting of the movement speed, and retractionto the outside of the scan area, together with the produced image data.

In this embodiment, the controller 21 serves as an image processorconfigured to produce image data indicating a two-dimensionaldistribution of intensity of the secondary charged particles detected bythe detector 16.

In the screen for moving the needle 18 by the user interface 22, forexample, the controller 21 causes the cursor of the user interface 22 tobe displayed on the produced image data. The cursor is operated by theoperator through an input operation made to the user interface 22, sothat the movement position, route, and the like of the needle 18 on theimage data are instructed. In accordance with the instructions, theneedle actuator 19 is actually operated to actuate and move the needle18.

The charged particle beam apparatus 10 according to the embodiment isconfigured as described above. Next, the operation of the chargedparticle beam apparatus 10 will be described.

The controller 21 controls the display device 20 to display an operationscreen 20A and an display screen 20B, as shown in FIG. 2, as screens foractuating the needle 18 by the user interface 22. A plurality of orfirst to fifth operation menus 31 a to 31 e the selection of which canbe switched by an operation of the user interface 22 are disposed in theoperation screen 20A.

When the first operation menu 31 a is selected, the controller 21 causesthe operation screen 20A of “Operation”, and the display screen 20Bhaving the latest image data and the cursor of the user interface 22 tobe displayed on the display device 20. The operation screen 20A of“Operation” is provided with menus 32 a to 32 c for instructing jogdrives (namely, drives which are continued without designating theactuating amount) of the needle 18 to be performed in the correspondingone of the X-, Y-, and Z-axis directions, and the direction of rotationabout the center axis. The operation screen 20A of “Operation” isprovided with menus 33 a to 33 d for giving various instructions to theautomatic movement of the needle 18. The menu 33 a of “Approach”instructs the needle 18 to automatically moving to the irradiation area.The menu 33 b of “Sequence” instructs the needle 18 to automaticallycontinuously move along a preset movement route. The menu 33 c of “Stop”instructs the needle 18 to stop the automatic movement. The menu 33 d of“Initial” instructs the needle 18 to automatically retract to areference position which is outside the irradiation area. The operationscreen 20A of “Operation” further is provided with menus (not shown) forchanging the movement speed of the needle 18.

The operation screen 20A of “Operation” is provided with a track menu 34for instructing execution of automatic continuous movement of the needle18 so as to track the movement of the cursor in the display screen 20Baccording to the operation of the user interface 22.

The display screen 20B has a cursor 42 for the user interface 22 whichis used for causing an image of the irradiation target (for example, aneedle image of the needle 18) 41 to perform track movement, on thelatest image data in which the needle image 41 is displayed.

In the case where the track menu 34 is selected in the operation screen20A of “Operation”, the controller 21 repeatedly acquires the positionof the cursor 42 which is moved in the display screen 20B in accordancewith a predetermined operation on the user interface 22, atpredetermined timings, for example, with preset intervals. Then, theactual needle 18 is driven by the needle actuator 19 so that the needleimage 41 on the image data sequentially tracks the positions of thecursor 42 which are acquired.

During scanning irradiation with the charged particle beam (the focusedion beam and the electron beam), i.e., during production of image data,the controller 21 enables the needle actuator 19 to actuate the needle18. In the case where the stage 12 is maintained to have a predeterminedposture state by the stage actuator 13, moreover, the controller 21enables the needle actuator 19 to actuate the needle 18. For example,the predetermined posture state is a state where the surface of thestage 12 is substantially perpendicular to the irradiation direction ofthe charged particle beam (the focused ion beam and the electron beam).

When, as sequentially shown in the upper, middle, and lower figures ofFIG. 3, the controller 21 sequentially acquires a first position A, asecond position B, and a third position C as the position of the cursor42 in the display screen 20B, for example, the target position of theneedle image 41 is sequentially updated in accordance with the positionof the cursor 42.

First, the first position A is acquired as the position of the cursor42, and then the controller 21 stores the positional coordinates of thefirst position A as the reference position.

Next, the second position B is acquired as the position of the cursor42, and then the controller 21 calculates the relative distance betweenthe positional coordinates of the second position B and the referenceposition. The positional coordinates which are obtained by adding thecalculated relative distance to the reference position are set as atarget position of the needle image 41 on the image data. Then, theneedle 18 is driven by the needle actuator 19 so that the needle image41 on the image data is moved to the target position at this timing. Asa result, the needle image 41 on the image data is moved from thecurrent position (i.e., the first position A) to the target position atthis timing (i.e., the second position B).

Next, the third position C is acquired as the position of the cursor 42,and then the controller 21 calculates the relative distance between thepositional coordinates of the third position C and the referenceposition. The positional coordinates which are obtained by adding thecalculated relative distance to the reference position are newly set asthe target position of the needle image 41 on the image data. Then, theneedle 18 is driven by the needle actuator 19 so that the needle image41 on the image data is moved to the target position at this timing. Asa result, the needle image 41 on the image data is moved from thecurrent position (i.e., the second position B) to the target position atthis timing (i.e., the third position C).

When the needle 18 is to be actuated by the needle actuator 19 using therelative distance with respect to the reference position which isobtained from the position of the cursor 42 in the display screen 20B,the controller 21 performs the control based on relative relationshipsbetween the irradiation directions of the focused ion beam and theelectron beam, and the actuating axes (i.e., the X-, Y-, and Z-axes)which are set with respect to the needle actuator 19.

Even in the case where the movement of the cursor 42 in the displayscreen 20B is faster than that of the actual needle 18, the controller21 performs the above-described process to move the needle image 41 onthe image data while tracking the cursor 42.

When, as sequentially shown in the upper, upper middle, lower middle,and lower figures of FIG. 4, the controller 21 sequentially acquires thefirst position A, the second position B, and the third position C as theposition of the cursor 42 in the display screen 20B, for example, thetarget position of the needle image 41 is sequentially updated inaccordance with the position of the cursor 42.

First, the first position A is acquired as the position of the cursor42, and then the controller 21 stores the positional coordinates of thefirst position A as the reference position.

Next, the second position B is acquired as the position of the cursor42, and then the controller 21 calculates the relative distance betweenthe positional coordinates of the second position B and the referenceposition. The positional coordinates which are obtained by adding thecalculated relative distance to the reference position are set as atarget position of the needle image 41 on the image data. Then, theneedle 18 is driven by the needle actuator 19 so that the needle image41 on the image data is moved to the target position at this timing. Asa result, the needle image 41 on the image data is moved from thecurrent position (i.e., the first position A) to the target position atthis timing (i.e., the second position B).

Next, the third position C is acquired as the position of the cursor 42at a timing before the needle 18 reaches the target position at thistiming, and then the controller 21 calculates the relative distancebetween the positional coordinates of the third position C and thereference position. The positional coordinates which are obtained byadding the calculated relative distance to the reference position arenewly set as the target position of the needle image 41 on the imagedata. Then, the needle 18 is driven by the needle actuator 19 so thatthe needle image 41 on the image data is moved to the target position atthis timing. As a result, the needle image 41 on the image data is movedfrom the current position (i.e., a position E between the first positionA and the second position B) to the target position at this timing(i.e., the third position C).

Namely, the controller 21 updates the movement instructions for theneedle actuator 19 at the timing when the new position of the cursor 42is acquired, and therefore the needle 18 in the real space is driven sothat the movement locus of the cursor 42 in the display screen 20B drawsa smooth curve while being subjected to so-called smoothing.

When the second operation menu 31 b is selected in the operation screen20A, the controller 21 causes the operation screen 20A of “Sequence”,and the display screen 20B having the latest image data to be displayedon the display device 20 as shown in FIG. 5. The operation screen 20A of“Sequence” is provided with menus 51 a, 51 b for instructing thesequential movement (namely, the automatic and continuous movement alongthe preset movement route) of the needle 18 to start and stop, and menusfor instructing addition and deletion of a movement route, and the like.

In a case where the menu 51 a for instructing the sequential movement tostart is selected in the operation screen 20A of “Sequence”, thecontroller 21 causes the needle actuator 19 to actuate the needle 18based on the current position of the needle 18 and the preset movementroute. For example, the controller 21 extracts the positionalcoordinates which are closest to the current position of the needle 18,from the plurality of positional coordinates constituting the presetmovement route, and the needle 18 is automatically moved from theextracted positional coordinates on the movement route.

When, as sequentially shown in the upper, upper middle, lower middle,and lower figures of FIG. 6, the movement route is set by the firstposition A, second position B, third position C, and fourth position Dcorresponding to a plurality of positional coordinates in the realspace, for example, the controller 21 first extracts the third positionC which is closest to the current position F of the needle 18.

Next, the controller 21 causes the needle actuator 19 to actuate theneedle 18 so that the needle 18 is moved from the current position F atthis timing to the third position C which is closest to the currentposition F.

Then, the controller 21 causes the needle actuator 19 to actuate theneedle 18 so that the needle 18 is moved in the movement direction (forexample, in the direction along which the needle is sequentially movedto the fourth position D, the third position C, the second position B,and the first position A) which is set on the movement route.

The display screen 20B of FIG. 6 may be an image obtained by an opticalmicroscope in place of an image data due to a charged particle beam. Inthis case, the charged particle beam apparatus 10 may include an opticalmicroscope which can observe the interior of the charged particle beamapparatus 10.

In a case where an adequate movement route of the needle 18 ispreviously set in the operation screen 20A of “Sequence”, the controller21 previously selects the actuating axis (or the actuating direction) ofthe needle actuator 19 with respect to the actuating of the needle 18,for each of the plurality of positional coordinates defining themovement route.

Alternatively, in the setting of the movement route, a registrationmethod in which the needle 18 is moved and the position after themovement is designated may be used in place of the registration methodin which the coordinates of a plurality of positions are designated.Namely, the needle 18 is moved, and, while visually checking that theneedle 18 does not interfere with the components of the charged particlebeam apparatus 10, for example, the focused ion beam column 14, thepositions after the movement are registered one by one. According to themethod, the needle 18 can be moved more safely.

When the third operation menu 31 c is selected in the operation screen20A, the controller 21 causes an operation screen (not shown) of“Correction of eccentricity” to be displayed on the display device 20.The operation screen of “Correction of eccentricity” is provided with aplurality of menus (not shown) for correcting a positional displacementof the needle 18 which is obtained from the rotation locus of the needle18 about the center axis.

The controller 21 elliptically approximates the eccentricity locus ofthe needle 18 by using the positions of the needle 18 for at least threeangles which are obtained when the needle 18 is rotated about the enteraxis by the rotation mechanism (not shown) of the needle actuator 19.For example, the controller 21 calculates a change of the position ofthe needle 18 at three or more different angles, by using a sinusoidalwave, whereby the eccentricity locus of the needle 18 is approximated toan ellipse or a circle. Then, the controller 21 corrects the positionaldisplacement of the needle 18 by using the eccentricity locus of theneedle 18, at each of the respective predetermined angles.

When the fourth operation menu 31 d is selected in the operation screen20A, the controller 21 causes an operation screen (not shown) of “Speedlimit” to be displayed on the display device 20. The operation screen of“Speed limit” is provided with a plurality of menus (not shown) forautomatically changing the actuating speed of the needle 18 inaccordance with the position, actuating amount, and the like of theneedle 18.

For example, the controller 21 performs settings so that, during thesequential movement of the needle 18, the actuating speed changes on adownward trend in accordance with the approach of the needle 18 towardthe end position of the movement route.

The controller 21 may cause the needle 18 to be moved by using a contactsensor function of the needle 18. For example, a change of the electricresistance when the needle 18 makes contact with a component of thecharged particle beam apparatus 10 or the sample S is detected, and thecontact is sensed. When a contact is sensed, the controller 21 stops themovement of the needle 18. This configuration enables the needle 18 tobe safely moved.

When the fifth operation menu 31 e is selected in the operation screen20A, the controller 21 causes an operation screen (not shown) of“Parameter” to be displayed on the display device 20. The operationscreen of “Parameter” is provided with a plurality of menus (not shown)for setting various parameters for the actuating of the needle 18 by theneedle actuator 19.

As described above, the charged particle beam apparatus 10 according tothe embodiment is provided with the controller 21 which causes theneedle 18 to be moved by tracking a change of the position of the cursor42 in the display screen 20B. Even in the case where the needle 18 ismoved while passing through a plurality of way points, therefore, it ispossible to prevent the operation from being complicated.

Moreover, the apparatus is provided with the controller 21 whichrepeatedly acquires the position of the cursor 42 at predeterminedtimings, thereby updating the target position. Therefore, the needle 18can be moved continuously and smoothly to the target position whilepassing through a plurality of arbitrary positions. Even when the numberof via positions is increased, moreover, the target position is updated,and therefore it is possible to prevent necessary information of thetarget position from being increased.

Hereinafter, a first modification of the above-described embodiment willbe described.

In a case where, in the above-described embodiment, the needle image 41on the image data is to track the movement of the cursor 42 in thedisplay screen 20B, the controller 21 may select the actuating axis (orthe actuating direction) of the needle actuator 19 in accordance withthe irradiation direction of the charged particle beam (i.e., thefocused ion beam and the electron beam).

Hereinafter, a case where the angle between the irradiation directionsof the focused ion beam and the electron beam is a predetermined angle(for example, an adequate angle between 50 degrees and 90 degrees, suchas 55 degrees), and the irradiation direction of the focused ion beam isparallel to the Z-axis of the needle actuator 19 will be exemplarilydescribed.

In this case, the image data obtained by the focused ion beam form animage on the X-Y plane configured by the X- and Y-axes of the needleactuator 19. The image data obtained by the electron beam form an image(for example, an image on the X-Z plane) which is inclined by apredetermined angle with respect to the Z-axis of the needle actuator19.

First, the controller 21 sets the target position of the needle 18 inaccordance with the position of the cursor 42 in the display screen 20Bby using the image data of the focused ion beam, and drives the needle18 by using only the X- and Y-axes of the needle actuator 19. As aresult, the needle 18 is moved to an adequate position in the Z-axisdirection including the actual target position.

By using the image data of the electron beams, then, the controller 21sets the target position of the needle 18 in accordance with theposition of the cursor 42 in the display screen 20B, and drives by usingonly the Z-axis of the needle actuator 19. As a result, the needle 18 ismoved from the adequate position in the Z-axis direction including theactual target position, to an actual target position.

In the case where the needle 18 is to be actuated by using the imagedata of the electron beams, the controller 21 may drive the needle 18 byusing also the X-axis in addition of the Z-axis of the needle actuator19 as required.

According to the first modification, the actuating axis (or theactuating direction) of the needle actuator 19 is selected in accordancewith the irradiation direction of the charged particle beam (i.e., thefocused ion beam and the electron beam), and therefore the actuating ofthe needle 19 in three-dimensional directions can be easily controlled.

Hereinafter, a second modification of the above-described embodimentwill be described.

In the case where, in the above-described embodiment, the needle image41 on the image data is to track the movement of the cursor 42 in thedisplay screen 20B, the controller 21 may select the actuating axis (orthe actuating direction) of the needle actuator 19 in accordance withthe scanning direction of the charged particle beam (i.e., the focusedion beam and the electron beam).

Hereinafter, a case where the scanning direction of the focused ion beamis caused to be rotated by a predetermined angle 0 with respect to theX-axis of the needle actuator 19 by, for example, the relative positionbetween the sample S and the needle 18 will be exemplarily described.

In this case, by using a relative distance (X, Y) with respect to thereference position which is obtained from the position of the cursor 42in the display screen 20B by the image data of the focused ion beam, thecontroller 21 provides the X- and Y-axes of the needle actuator 19 withmovement instructions (Xcos θ−Ysin θ, Xsin θ+Ycos θ).

According to the second modification, the actuating axis (or theactuating direction) of the needle actuator 19 is selected in accordancewith the scanning direction of the charged particle beam (i.e., thefocused ion beam and the electron beam), and therefore the actuating ofthe needle 19 in three-dimensional directions can be easily controlled.

Hereinafter, a third modification of the above-described embodiment willbe described.

In the case where, in the above-described embodiment, the needle 18 isto be sequentially actuated, when the current position of the needle 18exists in a predetermined positional area, the controller 21 may set arelative route which is based on the current position of the needle 18,with respect to the preset movement route. For example, thepredetermined positional area is an area where the relative route doesnot interfere with the components of the charged particle beam apparatus10.

When, as sequentially shown in the upper, upper middle, lower middle,and lower figures of FIG. 7, the movement route is set by the firstposition A, second position B, third position C, and fourth position Dcorresponding to a plurality of positional coordinates in the realspace, the controller 21 first sets the relative route. For example, thecontroller 21 extracts the third position C which is closest to thecurrent position F of the needle 18, from the plurality of positionalcoordinates constituting the preset movement route. With respect to theroute which is in the preset movement route, and which is subsequent tothe third position C, the controller 21 sets the relative route which isbased on the current position F of the needle 18.

Then, the controller 21 causes the needle actuator 19 to actuate theneedle 18 so that the needle 18 is moved in the movement direction (forexample, in the direction along which the needle is sequentially movedto the current position F, a fifth position G, and a sixth position H)which is set on the relative route.

In the case where the needle 18 reaches the end point (i.e., the sixthposition H) of the relative route, the controller 21 may cause theneedle actuator 19 to actuate the needle 18 in such a manner that theneedle 18 is moved to the end point (i.e., the first position A) of thepreset movement route.

According to the third modification, the control process in the casewhere the needle 18 is to be sequentially actuated can be simplified.

In the above-described embodiment, the controller 21 may be a softwarefunctional section, or a hardware functional section such as an LSI.

The technical scope of the invention is not limited to theabove-described embodiment, and is provided with configuration in whichvarious changes are made on the above-described embodiment withoutdeparting the spirit of the invention. Namely, the configuration of theabove-described embodiment is a mere example, and can be adequatelychanged.

What is claimed is:
 1. A charged particle beam apparatus comprising: acharged particle beam column configured to irradiate an irradiationtarget with a charged particle beam; a detector configured to detectsecondary charged particles emitted from the irradiation target by theirradiation with the charged particle beam; an image processorconfigured to produce image data indicating a two-dimensionaldistribution of intensity of the secondary charged particles detected bythe detector; a display device configured to display the image dataproduced by the image processor; a needle arranged in an irradiationarea of the charged particle beam; a needle actuator configured toactuate the needle; a user interface configured to receive an operationinput of an operator and set a target position of the needle on theimage data in accordance with the operation input; and a controllerconfigured to control the needle actuator to actuate the needle inaccordance with the target position that is set by the user interface,wherein the controller controls the needle actuator to move the needleto track a change of the target position that is set by the userinterface.
 2. The charged particle beam apparatus according to claim 1,wherein the controller is configured to repeatedly acquire the targetposition at predetermined timings and to update the target position. 3.The charged particle beam apparatus according to claim 1, wherein thecontroller is configured to control the needle actuator to set anactuating direction in accordance with an irradiation direction of thecharged particle beam, and wherein the charged particle beam comprises afocused ion beam and an electron beam the irradiation directions ofwhich are set with a predetermined angle with respect to one another. 4.The charged particle beam apparatus according to claim 1, wherein, in acase where a scanning direction of the charged particle beam is changedto have a predetermined angle with respect to an actuating axis of theneedle actuator, the controller controls the needle actuator to set theactuating direction of the needle in accordance with the scanningdirection of the charged particle beam.
 5. A charged particle beamapparatus comprising: a charged particle beam column configured toirradiate an irradiation target with a charged particle beam; a detectorconfigured to detect secondary charged particles emitted from theirradiation target by the irradiation with the charged particle beam; animage processor configured to produce image data indicating atwo-dimensional distribution of intensity of the secondary chargedparticles detected by the detector; a display device configured todisplay the image data produced by the image processor; a needlearranged in an irradiation area of the charged particle beam; a needleactuator configured to actuate the needle; a user interface configuredto receive an operation input of an operator and set sequential targetpositions of the needle on the image data in accordance with theoperation input; and a controller configured to control the needleactuator to actuate the needle in accordance with the sequential targetpositions set by the user interface, wherein, when an original targetposition is changed to a new target position on the image data beforethe needle reaches the original target position, the controller controlsthe needle actuator to track the change of the target position and movethe needle toward the new target position bypassing the original targetposition.
 6. The charged particle beam apparatus according to claim 5;wherein the user interface includes a cursor movable to the targetpositions on the image data; and wherein the controller is configured torepeatedly update the target positions at predetermined timings inaccordance with the position of the cursor.
 7. The charged particle beamapparatus according to claim 5; wherein, in a case where a scanningdirection of the charged particle beam is changed to have apredetermined angle with respect to an actuating axis of the needleactuator, the controller controls the needle actuator to set theactuating direction of the needle in accordance with the scanningdirection of the charged particle beam.
 8. The charged particle beamapparatus according to claim 5; wherein the charged particle beam is anion beam.
 9. The charged particle beam apparatus according to claim 8;wherein the controller is configured to control the needle actuator toset an actuating direction thereof in accordance with an irradiationdirection of the ion beam.
 10. The charged particle beam apparatusaccording to claim 5; wherein the charged particle beam is an electronbeam.
 11. The charged particle beam apparatus according to claim 10;wherein the controller is configured to control the needle actuator toset an actuating direction thereof in accordance with an irradiationdirection of the electron beam.